Sarex Vol. 10, Issue 39, July 2017 www.sarex.com Chemistry Behind Good Feelings
CNTENTS 1 Yuvi-cell 2 Reduclear-NS 3 Nylolevel-606 (Conc) UV Protective Finish Reduction Clearing Agent with No Smell Nylon Leveling Agents (Migration)
Yuvi-cell - UV Protective Finish Protection of skin against the action of solar radiation is relatively zone layer in the atmosphere blocks the UV radiations emitted a new buzz in textile finishing. Textiles are second skin to from the sun acting as a shield that prevents these radiations humans which are wore to safeguard the skin from external from falling on the earth's surface. But, due to the emission of agencies like wind, water, sunlight etc. Since all the textile greenhouse gases which has led to the depletion of ozone layer, substrates do not guarantee adequate protection, special allows these harmful radiations to fall on the earth's surface. finishes are required to enhance their properties. Ultraviolet Ultraviolet radiations accelerate the physical and chemical radiations constitute a very low fraction in the solar spectrum but deterioration processes of the polymeric substances such as influence all living organisms and their metabolisms. These fading of colorants, yellowing of cellulosic's, photo-oxidation of radiations can cause a range of effects from simple tanning to polyolefin's, embrittlement of coatings etc. Photo-degradation is highly malignant skin cancers, if unprotected. UV protection observed in almost every plastic material upon prolonged textiles include technical textiles, various apparels, accessories, exposure to sunlight, thereby restricting their application for such as hats, shoes, and shade structures such as umbrellas. outdoor use. The degradation can be minimized by using UV stabilizers, which dissipate the energy acquired from these Ever increasing demand in the marketplace for lightweight ultraviolet radiations in the harmless manner thus protecting the apparel that offers protection to human skin is increasing. material and getting themselves destroyed in the process. Looking beyond the physical appearance and feel of the fabric, today's end user is demanding for various functionality in a Clothing made from woven fabrics can provide convenient garment or a textile material. Due to this, clothing manufacturers personal protection, however not all fabrics offer sufficient UV are also focusing their attention in imparting performance and protection. Deep dyed fabrics show excellent protection from UV functional finishes to the fabric which meets the requirement of radiation. Sun protection involves a combination of sun the customer. These finishes help in enhancing the performance avoidance and the use of protective garments and accessories. of the wearer. ne such finish is UV protective finish which helps Reducing the exposure time to sunlight, using sunscreens and in protecting the skin from the harmful radiations emitted from protective clothes are the three ways of protection against the the sun. Garment construction can also help to increase the deleterious effects of UV radiation. protection from radiations by choosing suitable fibre and construction but that is not enough, so a chemical treatment is UV radiation degrades the textile materials due to excitations in required to enhance the UV protection of fabrics. some parts of the polymer molecule. Much depends on the type of fibre and its chemical structure. 3
Due to large surface area available, textile fabrics are more susceptible to attack by UV radiation. Natural fibres viz., cotton, silk, and wool have lower degree of Ultraviolet Protection Factor (UPF) absorption than synthetic fibres. Cotton fabric in grey state provides a higher UPF because of natural pigments, pectins and waxes. Dyed cotton fabrics exhibit higher UPF and undyed bleached cotton yields very poor UPF. UV radiation attacks polyamides the most by photo oxidation. The fabric looses its strength and its crystalline structure. Polyester too gets affected by UV radiation to the tune of 5-50% after 30 days of exposure. Polyester fibres absorb more in the UVA and UVB regions than aliphatic polyamide fibres. Bleached silk and bleached Poly Acrylonitrile show very low UPF of 9. and 3.9 respectively. UV protective finish are very integral for outdoor wear, active wear, parasols, beachwear, work wear etc. Work Wear Parasols Beach wear Active wear Solution from Sarex: Ultraviolet protecting factor testing: Understanding the requirement of today's generation and the The UPF values of the unfinished and finished fabrics were exigency for protection against harmful UV radiations to the end measured using a Shimadzu UV-2600 series in the range of 280 users, Sarex has developed an Ultraviolet protecting agent to 00 nm, Model UV- 2600 (A1166510136). The UPF values of Yuvi-Cell for cellulosic substrates which give very good Sun each fabric were determined from the total spectral Protection Factor (SPF). Cellulosic substrates treated with Yuvi- transmittance based on AS/NZS 399:1996 method. UPF was Cell exhibits excellent ultraviolet absorbing properties which are calculated using mean percentage transmission in the UVA also durable to home launderings. It can be applied on dyed region (315 to 00 nm) and mean percentage transmission in the fabrics with minimum shade change. UVB region (280 to 315 nm). The fabric is rated according to UPF. UPF is like SPF, except UPF rates protection against both Application of Yuvi-Cell on various cotton substrates: UVA and UVB. Technical textile with a UPF of 50, allows only Various quality of cotton fabrics were taken and padded with 1/50 of the UV radiation falling on the surface of the substrate to 70gpl Yuvi-Cell, adjusting the pick-up to 65-70% and pass through it. In other words, it blocks 98% of the UV radiation. maintaining the bath ph in the range from 5.0-6.0. These fabrics Sun protection clothing is an easy and steadfast form of UV o were further dried at 130-160 C. th protection and so is becoming more and more fashionable. Table 1: Grades and classification of UPF UPF Rating Protection Category UV radiation Blocked UPF 15 2 Good 93.3 95.9% UPF 25 39 Very Good 96.0 97.% UPF 0 50+ Excellent 97.5 98+%
Results and Discussion: Results in Table 2 show that the fabrics treated with Yuvi-Cell shows excellent UPF than the unfinished fabrics. This is due to strong absorption and blocking of UV rays in the near UV region. rganic products like benzotriazole, hydro benzophenone and phenyl triazine are primarily used for coating and padding processes in order to achieve broad protection against UV rays. The UV protection offered by a textile material is a synergistic influence of chemical characteristics, physico-chemical type of fibre, presence of UV absorbers, construction of fabric, thickness, porosity, extension of the fabric, moisture content of the fabrics, colour and the finishing given to the fabric. Table 2: UPF rating of various finished and unfinished cotton fabrics Sr. No. Colour 1 White 2 3 5 6 Finished UVA (315-00nm) UVB (290-315nm) UPF (290-00nm) Unfinished 25.17 18.69.97 Yuvi-Cell (70gpl) 5.02 2.05 8.71 Unfinished 5.56.38 22.01 Yuvi-Cell (70gpl) 1.75 1.12 87.61 Unfinished 6.22 2.9 28.78 Yuvi-Cell (70gpl) 1.1 0.92 107.17 Unfinished 11.3 10.25 9.53 Yuvi-Cell (70gpl) 2.99 2.09 51.26 Unfinished 3.15 1.98 19.25 Yuvi-Cell (70gpl) 2.26 1.61 59.28 Unfinished 12.28 8.36 11.56 Yuvi-Cell (70gpl).09 3.13 30.21 Maroon Purple Blue Yellow Striped Shirting Fabric finished with Yuvi-Cell showed durability upto 15 Home Launderings. To cope up with the current scenario and meet the requirement of the customers, which are ever increasing, such kind of finish can be very important. Today, human beings are more aware and concerned about health and the purpose of clothing has changed from basic need to enhance the performance. Recreational exposure accounts for most of the significant UV Radiation exposures of the population, and occupational exposure is also significant. This necessitates the development of stronger UV absorbers and thus Sarex has developed a UV protective agent i.e. Yuvi-Cell which can protect the wearer from the harmful UV radiations and also increase the life of the clothing. 5
Reduclear-NS - Reduction Clearing Agent with No Smell Last few decades have seen significant growth in consumption Dyeing of polyester is difficult due to the following factors: of synthetic fibres globally. Consumers highly prefer 1. High crystalinity characteristics such as durability, better stain resistance, 2. Hydrophobicity softness, and elasticity in their fibre uses. Manufacturers ability 3. Absence of chemically active group to provide all such properties at lower costs is one of the key driving factors for the growth of the global synthetic fibre market. Disperse dyes are the most important class of dye used in In addition, changing fashion trends are also expected to have dyeing of polyester fibres and provide a wide range of hues with perceptible effects on the global synthetic fibre market. good build-up and fastness properties. Disperse dyes are non ionic in nature with low aqueous solubility at dyeing temperature. USD 115 Billion, 2020 USD 73.5 Billion, 201 These dyes are applied in the form of an aqueous dispersion. Different methods of Polyester dyeing are as below: 1. Carrier dyeing 2. High temperature high pressure dyeing 3. Thermo-fixation dyeing. Solvent dyeing system Among the synthetic fibres, polyester is the most important and Irrespective of method of dyeing of polyester with disperse dyes, widely used due to its high strength, dimensional stability, unfixed disperse dyes remains on to the fibre surfaces after abrasion resistance, resiliency, as well as suitability for blending dyeing, which will considerably reduce wash fastness, with natural fibres. According to Zion Research, the Polyester sublimation fastness, dry cleaning fastness as well as dulling of market was valued at USD 73.5 Billion in 201 and should be the fabric shades. In order to remove unfixed disperse dye, worth USD 115.0 Billion by 2020. Polyester has also high conventional reduction clearing is carried out with caustic and chemical resistance, moth proofness and excellent Wash & hydrose (Sodium dithionite) at 70 C for 10-20 min. The Wear and permanent press characteristics. These unique treatment with caustic and hydrose is often sufficient to clear the properties make it the largest trade fibre in the synthetic fibre fibre surfaces but the ease of removal varies from chromophore world. Polyester fabric when blended with cotton and wool, gives to chromophore of the dyestuff used in study. high quality fabric. 6
Sodium dithionite has setback due to generation of sulphites and Unique features: sulphates. High concentrations of sulphate increases TDS in Reduclear-NS is available in powder form with no odour. Works under acidic ph hence alkalifying the bath and fresh effluent. It causes corrosion of the drainage system and has obnoxious odour. post-cleaning treatment is not require. In order to overcome these disadvantages of reduction clearing Dyeing followed by reduction clearing in the same bath is by caustic hydrosulphite, Sarex has developed a concentrated possible. reduction clearing agent Reduclear-NS which works under Saves time, energy, and water. Elimination of subsequent neutralisation helps in reduction acidic ph and is free from unpleasant smell or odour. of TDS in effluent. Experimental % Shade Disperse Dye Recipe-1: Navy Blue shade Recipe-2: Maroon shade C.I. Disperse Red 165 0. % 2.90 % C.I. Disperse range 30 0.8 % 1.1 % C.I. Disperse Blue 79:1 3.6 % 0.26 % Dyeing of polyester was carried out with Recipe-1 and Recipe-2 by maintaining the dye bath ph of.0-.5 at 130 C for 5 min. After the completion of dyeing, Reduction clearing (RC) was carried out by conventional method i.e. with 2g/l Caustic + 2g/l Hydrose and with 0.75g/l of Reduclear-NS. Process flow diagram of dyeing of polyester followed by reduction clearing Conventional system Reduclear-NS RC with 2g/l Caustic + 2g/l Hydrose RC with Reduclear-NS 1300C, 5 min 1300C, 5 min 800C, 25 min 800C, 20 min 10-20 min 500C, 10 min Rinse-cold (If required) R/C DYEING HT WASH 2 g/l Caustic & 2 g/l Hydrosulfide R/C NEUTRALIZE DYEING 0.5 g/l Reduclear-NS 0.5 g/l Acetic Acid 7
Table 1: Colour strength and shade change values of maroon and navy dyed fabric Colourant strength (%) de Da Db Conventional (2g/l Caustic + 2g/l Hydrose) 100 0.75g/l Reduclear-NS 102 0.691 0.570 0.376 Conventional (2g/l Caustic + 2g/l Hydrose) 100 0.75g/l Reduclear-NS 102 0.605 0.66 0.385 Fabrics Maroon shade Navy blue shade Table 2: Grey scale rating for colour staining Fabrics Wool Acrylic Polyester Nylon Cotton Acetate Conventional (2g/l Caustic + 2g/l Hydrose) 0.75g/l Reduclear-NS Conventional (2g/l Caustic + 2g/l Hydrose) 0.75g/l Reduclear-NS Maroon shade Navy blue shade Both the reduction cleared fabrics were subjected for fastness studies. The washing fastness was performed by IS 105 C06-C2S. Table 3: Washing fastness - IS 105 C06-C2S Maroon shade Dyed fabric 8 Staining on Multifibre Navy blue shade Dyed fabric Staining on Multifibre 2 g/l Caustic + 2 g/l Hydrose 2 g/l Caustic + 2 g/l Hydrose 0.75 g/l Reduclear-NS 0.75 g/l Reduclear-NS
Nylolevel-606 (Conc) - Nylon Leveling Agents (Migration) Polyamides refer to various natural (polypeptides) and synthetic operation. Suitable leveling assistants include oleyl materials containing free amino groups. Examples of sulphonates, fatty alcohol sulphonates, fatty acid condensation polyamides include nylons, wool, and silk. Nylon fibre is products, alkyl and alkyl aryl poly glycol ethers and surface- commonly dyed with acid dyes which are anionic in character, active chemicals in general. including premetallized acid dyes, in a batch process referred to as exhaust dyeing. For example, nylon fibre which has been Unlevelness is caused by: made into fabric may be dyed in a jet-dyeing machine, whereby a continuous loop of the fabric is circulated throughout the dye bath by impinging the dye bath liquor against the fabric in a venturi nozzle. Care must be taken during the dyeing process to obtain a uniform distribution of dye on the fabric, referred to as leveling. High and varying affinity of the dye on the fibre. High and varying affinity of the fibre for the dye. Uneven distribution of the dye solution on the fabric / fibre. Temperature differences on the fabric or fibre. Since acid dyes are negatively charged, the dyes are attracted to Insufficient levelness can be prevented by means of suitable positive dye sites appearing in the targeted substrate. In dyeing techniques and by means of leveling assistants. general, acid dyes have a high affinity for protonated polyamide materials, meaning that the dyes have a strong tendency to Leveling assistants reduce mainly the rate of dyeing, increase quickly bind to the polymer. Unfortunately, however, once in the rate of dye migration within the fabric and improve the contact with the cationic polymer surface, acid dyes have a compatibility of the dyes. tendency to poorly diffuse into the polyamide. In such cases leveling agents which works on migration principle works Leveling assistants can exert two or more of the above effectively. mentioned effects at the same time. Leveling assistants can be divided into two groups, those which have an affinity for the fibre Leveling agents or assistants are generally surface-active textile and those which have an affinity for the dye. Leveling assistants dyeing auxiliaries which have the task of (i) thoroughly wetting with an affinity for dyes form an addition compound with the dye the fibre/ fibre blend to be dyed (ii) promoting penetration of the whose stability is concentration dependent and normally fibres and (iii) preventing too rapid uptake of the dyes, which can decreases with increasing temperature. lead to unlevelness (spottiness) during the dyeing 9
The dye distribution equilibrium between the dye in solution and Migration of applied dyes in a uniform manner throughout the the dye in the fibre is therefore shifted to the dye in solution. The dyed goods is called leveling and it may be a property of the dye increased dye concentration in the dye solution makes it or it may require some chemical assistance. Understanding the possible for regions of the fabric which were dyed in a non-level need, Sarex has developed a product Nylolevel-606 (Conc), an manner to level out as a result of dye migration. excellent leveling agent for polyamide fabrics which works on dye migration principle. Effective leveling assistants have an affinity for the dye that is Unique features: sufficient to reduce the absorption rate or to speed the migration rate. Differences in the absorption behaviour of different dyes can likewise be levelled, so that the dyes in a dye mixture can go on at a uniform rate. Assistants with an affinity for dyes can also be used to level previously dyed materials. Assistants with an affinity for fibres go onto the fibre in competition with the dye. This competition reaction reduces the absorption rate and promotes the migration rate. Leveling agent for polyamide fabrics. Excellent migration imparting level dyeing. Corrections of faulty dyeing. Application: Exhaust: Recommended dosage during dyeing of polyamide fabrics with Acid dyes. Important dye-affinity leveling agents for polyamides are Nylolevel-606 (Conc) : 0.5-1 % nonionic surfactants, cationic compounds or ethoxylated compounds. Important fibre-affinity leveling agents for polyamides are cationic compounds. Migration study: The efficiency of the product is evaluated by migration study. Polyamide fabric was initially dyed with 3.5% C.I. Acid Red 1. In every dye house, levelness of the dyeing is a major criteria, since unleveled goods are usually not saleable, causing loss to the manufacturer. Dyed (Fabric-1) and Undyed (Fabric-2) polyamide fabrics were o treated together with 0.5-1% Nylolevel-606 (Conc) at 98 C for 30 min. and the amount of dye migrated on the undyed fabric was evaluated. More the migration of dye on Fabric-2, better is the leveling property. Blank Fabric - 1 With 0.5-1% Nylolevel-606 (Conc) Fabric - 2 Fabric - 1 Fabric - 2 The above figure show excellent migration of dye on the fabric resulting into level dyeing. 10
Retardation study: Dyeing of polyamide was carried out with 2% C.I. Acid Blue 83 at various temperatures i.e. 50oC, 70oC, 90oC, 98oC, 98oC, 15 min and 98oC, 30min. The quantity of dye remaining in the dyebath i.e. retardation property was evaluated by performing second dyeing in the exhausted bath at 130oC for 30-5 min. Retardation curve 10 Colour value, K/S 120 Blank dyeing 100 0.5-1% Nylolevel-606 (Conc) 80 60 0 20 0 50 C 70 C 90 C 98 C 98 C/15 98 C/30 Temperature, C From the graph (Retardation curve) it could be seen; In blank dyeing, maximum amount of dye has been rushed onto the fabric as it reaches near to the dyeing temperature i.e. 90oC. This rushing of dye causes unlevel and patchy dyeing. Addition of Nylolevel-606 (Conc) in the dye bath show clear retardation of the dye at this temperature which in turn results into level and uniform dyeing. 11
CNTACT US Corporate ffice: 501, Waterford Building, C Wing, C D Barfiwala Marg, Juhu Lane, Andheri (W), Mumbai - 00 058, India. Tel.: +91 22 6128 5566 Fax: +91 22 218 350 Email: tcmktg@sarex.com Web: www.sarex.com Plants: N-129, N-130, N-131, N-132 & N-232, MIDC, Tarapur - 01 506, India. C E R T I F I C A T I N S Certificate No. T-2718 M&S REACH HSAS 18001:2007 IS 17025:2005 IS 1001:200 IS 9001:2008 TW STAR EXPRT HUSE GTS